Complete the following passage by using

Complete the following passage by using the words in the box. Each word can only be used once. Note that there is one word more than you need.

A. roots      B. but      C. covered      D. reproduce    E. energy F. probably   G. gaining   H. surrounding   I. supplied      J. life

Life on land probably began about 430 million years ago, though it has existed in the water for perhaps as much as 3,000 million years. When we think of the first     小题1:    on land, we     小题2:   think of strange animals coming out of the oceans, but, in fact, no animals could have been living if plants had not been on land first. Plants had to be on land before animals arrived. They    小题3:  the first land animals with the    小题4:   and food necessary, since they ---the plants are the only form of life that is able to get and store    小题5:    .
The first plants to exist out of the water were probably certain kinds of algae （ 藻类 ）which were followed by other plants that grew close to the ground and needed water in which to   小题6:  . Once the move to land has been made, however, evolution took place quickly. By the end of 100 million years, plants had developed their    小题7:  , and some have got tree-like forms since height was very important in    小题8:  sunlight. About 300 million years ago, much of the world was     小题9:   with forests of huge trees. In most ways they were like modern trees. They had roots, leaves, wood, but mostly they had not developed seeds.